One in five strokes occurs in the posterior circulation, whose blood vessels (the vertebral and basilar arteries) supply the back of the brain. We have shown that posterior circulation TIA and minor stroke is followed by a high risk of further stroke.
One in five of these strokes is caused by narrowing of the vertebral arteries. Narrowing of the carotid artery (which supplies the front of the brain) can be successfully treated by surgery preventing further strokes. Surgical access to the vertebral arteries is difficult but it is now possible to access the narrowing by passing a wire up the artery and opening up the narrowing using a stent.
In pilot studies we and others have shown vertebral stenting appears to be relatively safe. It is now essential to evaluate in a large trial whether vertebral stenting prevents recurrent stroke. If so this treatment would be applicable to a large number of stroke and TIA patients.
In a number of specialised centres in the UK who already have expertise in stenting we will perform a feasibility study to confirm that the procedure is safe and allow us to plan a large definitive study in this area.